package com.u2b.business.location;

import java.text.DecimalFormat;

public class BaseLoactionService
{

    private final static double EARTH_RADIUS = 6378.137;
    private DecimalFormat decimalFormat;

    private static double rad(double d)
    {
        return d * Math.PI / 180.0;
    }

    public double getDistance(double lat1, double lng1, double lat2, double lng2)
    {
        double radLat1 = rad(lat1);
        double radLat2 = rad(lat2);
        double a = radLat1 - radLat2;
        double b = rad(lng1) - rad(lng2);

        double s = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(a / 2), 2) + Math.cos(radLat1) * Math.cos(radLat2) * Math.pow(Math.sin(b / 2), 2)));
        s = s * EARTH_RADIUS;
        s = Math.round(s * 10000.0) / 10000.0;
        decimalFormat = new DecimalFormat("#.00");
        String st = decimalFormat.format(s);
        return Double.parseDouble(st);
    }

}
